I need to see how to 0solve the problem I am having problems
How To Find The Missing Number When You Use The Mean Number? 12, , 17; Mean : 14
S,12,3,15,13,?
It looks like you have 3 numbers whose mean is 14. Let x be the missing number.
(12 + 17 + x)/3 = 14 (the mean of the numbers is 14)
12 + 17 + x = 3*14 (multiply both sides by 3 to get the sum of the numbers)
x = 3*14 - 12 - 17 (subtract 12 and 17 from both sides. That is, subtract the numbers you know from the sum to find the number you don't know.)
x = 42 - 12 - 17 = 30 - 17 = 13 (evaluate)
The missing number is 13.
Check
(12 + 13 + 17)/3 = 14
(25 + 17)/3 = 42/3 = 14 (yes)
(12 + 17 + x)/3 = 14 (the mean of the numbers is 14)
12 + 17 + x = 3*14 (multiply both sides by 3 to get the sum of the numbers)
x = 3*14 - 12 - 17 (subtract 12 and 17 from both sides. That is, subtract the numbers you know from the sum to find the number you don't know.)
x = 42 - 12 - 17 = 30 - 17 = 13 (evaluate)
The missing number is 13.
Check
(12 + 13 + 17)/3 = 14
(25 + 17)/3 = 42/3 = 14 (yes)
